Stapling tool



March 28, 1950 w. E. WEMBER STAPLING TOOL 3 Sheets-Sheet l Filed March24, 1948 INVENTOR. WALTER E.WEM BER ATTORIS March 28, 1950 w. E. WEMBERSTAPLING TOOL Filed March 24, 1948 5 Sheets-Sheet 2` WALTER E. WEMBERATTORN YS March 28, 1950 w. E. wl-:MBER

STAPLING TOOL 3 Sheets-Sheet 3 Filed March 24, 1948 INVENTOR. WALTER E.WEM BER www om wwwwww ww ww www QN ww 0E www E www www w uw www. ww wwwwww w www w ww www www .ww ww ww www ww www www Lwww www TTORNESPatented Mar. 28, V1950 UNITED STATES PATENT IOFFICE STAPLING TOOLWalter E. Wembcr, Waukegan, Ill., assignor, by

mesne assignments., to National AutostitchCorporation, a corporation `ofIllinois Application March .24, 1948, Serial No. 16,809

12 Claims.

This invention relates to stapling devices or tools and particularly tostapling tools of the hammer type.

Hammer type stapling devices as heretofore manufactured have been thesubject of many objections despite the convenience with which they wereeffective to drive staples into the work. These objections have centeredin a large .measure about the difficulty and cost of manufacture and thelarge number of parts that were needed in such manufacture. It is,therefore, an important object of this invention to simplify themanufacture of hammer type stapling devices, and van object related tothe foregoing is vto enable such stapling devices to be constructed insuch a way as to involve but a very few parts that must be .made andfitted together at relatively close tolerances.

Other and related objects are to enable such hammer type staplingdevices .to be Vso constructed as to avoid the necessity for accuratepivotal connection of the two major yelements of the device; to simplifythe matching ofthe staple driving ram `with the guiding elementtherefor; to enable the ramand its guide to be mounted on a singleelement of the device; and to enable the staple driving action tob'eattained without marring of the surface in which the staple is driven.

In the use of stapling devices of the aforesaid character, theconvenience `of loading of the staples is of course an important factor,and it is therefore another important object of this invention tosimplify and facilitate the staple loading operation.

Other and further objects of the present invention will be apparent fromthe following description and claims and are illustrated in the'accompanying drawings which, by way of illustration, show a preferredembodiment yand the principles thereof and what I now consider to be thebest mode in which I have contemplated applying those principles. Otherembodiments of the invention embodying the same or equivalent principlesmay be used and structural changes may be made as desired by thoseskilled in the art without departing from the present inven tion and thepurview of the appended claims.

In the drawings:

Fig. 1 is a side elevational view of a stapling device embodying theinvention;

Fig. 2 is a vertical sectional view taken longitudinally of Fig. 1;

Fig. 3 isy a. vertical sectional view showi-ngv the 2 parts uponcompletion of a staple driving operation;

Fig. 4 is a horizontal sectional view taken along the line 4-4 of Fig.2;

Fig. 5 is a Vfront Yor yleft hand end elevational view;

Fig.. 6 is an enlargedr vertical lsection similar to Fig. 2, takenlalong the line 6--6 .of Fig. 5 and showing an enlarged portion of thestaple driving ram and the associated mechanism;

Fig. '7 is a vertical section taken along the line 'i-J of Fig. 6;

Fig.. 8 is a vertical section taken along the line B--il of Fig. 6;

Fig. 9 isa vertical section taken alongV the line 9 9 of Fig. 6;

Fig. i0 is a vplan section taken along the line t--l of Fig. 6;

Fig. l1 is a plan section taken along the line i--H of Fig. 6;

Fig.. 12 is a plan section taken along the line 1.2--12 of Fig. 6;

Figs. 13, 14 and l5 are fragmental vertical sectional views showingportions of the staple loading and advancing mechanism in diiere-ntpositions.;

Figs. 16, 17 and 18 are vertical sectional views taken respectivelyalong the lines `lili-AB, Huil and Iii-I8 of Fig. 13;

Fig. 19 is a fragmentary plan .section taken along the line l-9--l9'1ofFig. 13; and

Fig. 20 is a vertical section taken along the line 2li-2B of Fig. 14.

For purposes of disclosure the invention is herein illustrated asembodied in a hammer type stapling device or tool which comprisesa pairof elongated channel members 32 and 36 made from `sheet metal stampingsand arranged with the lower channel 32 disposed in a partially housedrelation within the upper channel 34, and theseY channels 3.2 and 34 arepivoted together at their right hand or .rear ends by pivot screws 35 sothat in a staple driving operation the forward or left. hand end of theupper channel 34 may.

move downwardly with respect to the channel 3'2 from the position ofFig. 2 tothe position 'of Fig.. 3.v

The right hander rear portion of the upper :cham nel 34A constitutes thehandle portion or the device or tool, and while grasping this handle thetool is swung downwardly through a hammer'- like driving stroke so thatthe lower Vleft hand face. of the-lower channel 32 is broughtintocontact with the surface-of the work, such as a pair of .superposedWork pieces W--l and W-2. which are to be connected together by a stapleThe staples S as herein shown are of the type wherein the upper crossbarI has two legs of equal length extended downwardly therefrom, but itwill be understood that conventional staples having legs of unequallength may be employed where this is desirable.

The lower channel member 312 is utilized under the present invention tocarry the staple holding and feeding means F and the staple driving rammechanism R, such ram mechanism being disposed on channel 32 adjacent tothe left hand or forward end as shown in Figs. 1 to 3 of the drawings.The other or upper channel member 34 serves primarily as a housingmember and as a handle, since the right hand or rear end of this upperchannel 34 is grasped by the user when the tool is to be utilized rtodrive a'staple into the work.

The upper channel 34 is formed so as to be of substantially uniformcross section throughout most of its length, but at its forward or lefthand end as shown in Figs. 1 to 3 of the drawings, the channel 34 has anupward extension 34E whereby operative clearance is provided within thechannel for elements of the ram mechanism R (Fig. 3), as willhereinafter be described. The upper channel 34 has a top wall 34T, aforward end wall 34F and a rear end wall 34R, and at the opposite edgesof the top wall 34T, side walls 34S are extended downwardly and areconnected to the end walls 34F and 34R. Near the rear wall 34R, a bottomwall 34B is provided for a limited distance between the lower edges ofthe side walls 34S, and in the plane of the bottom wall 34B, each of theside walls 34S has an inwardly extended guide flange 34G which, as willbe evident in Fig. 4 of the drawings, extends in a forward or left handdirection throughout -a substantial portion of the length of the channelmember 34. However, at a point spaced a short distance from the lefthand or forward end of the member 34, the flanges B4G are terminated asat 34C so as to afford a clearance opening in this area that is of thefull width of the channel and this clearance opening, and the flangesB4G, are important, as will hereinafter be described, in permittingready assembly of the parts as well as in attaining a guiding actionbetween the parts after such assembly.

The lower channel 32 is formed so las to face upwardly and this channelhas, in the left hand or forward portion thereof, a true channel form,while at the right hand end portion, the web or cross member of thechannel is cut away to afford clearance to facilitate loading of staplesS into the staple holding and feeding mechanism, as will hereinafter bedescribed. In this portion it will also be noted that the vertical widthof the side walls 32S has been reduced so that the handle portion of thechannel 34 may be grasped without contact with the side walls 32S. Thus,the lower channel 32, in the forward or left hand portion thereof, has abottom wall 32B and upstanding side walls 32S, and these side walls areso spaced that they have what may be termed a loose sliding fit againstand between the two guide flanges 34G of the upper channel 34. Thebottom channel wall 32B terminates at its rear end at 32T substantiallymidway between the ends of the member 32, and from the edge 32T andsubstantially to the forward or left hand end of the channel 32, astaple supporting and guiding means is provided within the channel andon top of the bottom wall 32B. This guiding means may be attained in asimple manner through the mounting of a channel member 38 within thechannel 32, and with the cross wall or web of the channel 38 secured asby means of screws 3B disposed within the channel 38 and extendedthrough the bottom wall or web thereof into the bottom wall 32B of thechannel 32. The side walls of the channel 38 are spaced from the sidewalls 32S of the channel 32 so that the legs of the staples S may ridebetween the channel 33 and the walls 32S, and when the staples S are inthis position, the cross members of the staples extend across the opentop of the channel 38 and ride upon the upper edges of these side walls,as shown in Fig. 9 of the drawings. When the staples S are in thisposition, they are held downwardly with respect to the channel 38 byguide plates 4B that are secured as by welding to the inner faces of theside walls 32S.

The staples S that are thus supported and guided on the channel 38 arenormally urged in a forward or left hand direction, Fig. 2, by astaple-advancing follower mechanism that includes a channel shapedfollower 4| that rides A on the channel 38 and within the spacetraversed by the staples S. The follower 4| has the web portion thereofarranged to ride on the upper edges of the side walls of the channel 38,and lianges 4|F on the follower 4| ride in the spaces I between the sidewalls 32S and the channel 38.

On the web of the follower 4| a bracket 42 is secured, and an elongatedactuating rod 43 is slidably extended through the bracket 42longitudinally of the channel 32. This rod 43 extends E. rearwardly orto the right through an upwardly faced spacing channel 45 that isdisposed between head 43H formed thereon so that by withdrawing the rod43 in a rearward or right hand direction the follower 4| may bewithdrawn from its position within the staple guideway. This operationis facilitated through the provision of a knurled head 48 that isscrew-threaded onto the rear or right hand end of the rod 43. To enablethis to be done, a clearance opening 34C is provided in the rear wall34R of the upper channel. The head 48 has a flange 48F formed thereon soas to be disposed within the channel 34, and a spring latch 49 securedto the web of the channel 45 is arranged to engage this flange to latchthe rod in its forward or left hand position as shown in Fig. 2.

When the tool is to be loaded with staples, the handle 48 of the rod 43is grasped and the follower 4| is withdrawn, and when the follower hasbeen completely moved out of the staple guiding channel or passage therod 43 is tilted so as to move the follower 4| upwardly into a clearancespace 50 formed between the plates 4D and the channel 45, such clearancespace being shown in Fig. 2, and the location of the follower 4| in suchclearance space being illustrated in Fig. 14 of the drawings. Withrespect to this positioning of the follower 4| it should be observedthat the lower face of the web of the channel 45 is disposedsubstantially in the plane of the lower edges of the guide plates 4U,and the lower edges of the flanges 4|F of the follower are disposedoelrfeislieh-tf distance above` thislplerie; ther .hief eolireeaare i .i.ci groeps-,orf 1mi-te oonrentona es hionfm. read. y; loaded eta thetool. merely leef:-Y plao1...g;, the. 1.11. .rtedipoeition tonoitliewele,

Imelr 4.5;'. These Staples-may,

werdlt-orfto, th

ureethefster the guide n.

.. ,M ,f W 5.1.

eairwardy exten ons. of the lower chan 32 an the.u o

webnortion reihe-Spesen member; 45 is located. above-f medewer-edges..ofrthe rearward. eXtensonsof-f thelower member 32das*clearly:fllustratednin-EieSl 2.. and 1.6; ofthe: drawings .andwhenthe tool is.inrertedzzforfloedf f inapurposes1the--welo; of.` the Spacermeinber- 45,; aclantedfto., sunioort-- areroup. ci staples: in: 130:-,Sition for.A` feeding; onto; the Stanley Supporting;member-which,sfmounted upon-.thefbottomvo-fg therlowerfohannelmember-B2` at thefffront por.-

tion. thereof:`

The desirerif pivotal connection.=.betweenf,the: Channels, 3.121',-anda; 351:, and, atthe yright hand or; rear enel:vv thereoit is:vafforded .by meanethat-are-z best hownrin Eiger-1, 1 7 and: 1.9,.'yThus,.,itwi11. be. eridenti thatthe. eide., Walls.: 3.415-v arerecessed.. atfv 55ste receive theV h eadsdof;y the frnountingfpivot;Studs orfsorews 3.5:- Whoh-- here shouldered; poreytiene;extendineethroueh pirotorenines provided, ettliefbottoms,of-.thereoesses 5.5., andtheithreaded, portions of the pivot screws orstuds-j; 355;.. arey threaded.; into. they Side walls. 32S/ 2- and. theSide anees; or thepeoine. ebennelff It-,Wilifbe v.olo- Servedfthetfet:thefeortione Surrounding Vthe pir-- ots-A1. 3'5, tljiegv side walls 32Sare,somewhaty thick-v eedf a-Sfet; 32T., Feeeendr 1.9, and: therefo.refIwhensthegdevice--isto be assembled; thi-sgthicls eneii, portionisinsertediinto the Vo-leararioe.Sioeoe forwardly/oi the endsrMC-ojf theiiangesv 346;,- and A thelowerfobennel 3,2` is.fthenmovedlloneitildnallrinterne,- Qhan-nei aauntii .therthicrened perdons., 32,'11.L aredisposed in,4 the-proper; position j for'fin.- sertionzof the; pivot,screwsI 35p Thepresent invention aiordsI anhextrernelyy simpleway vinwhich to afford accuratecooperari. tionQoi theieleinents of theram.meohanisni- R,k audio acoomplishneths-,the rammeohanism, isproydeflvwith. a relatively, simple.. but., dei, curately forrried,l casting ormachined-:element-in theuform of` ayer-tical bar-60 which actsas aguid;

ingelement. The. bael) isdisposed betweenthe forward edges off. th'e..side.v wal-ls 32.S, and this ban 60;.-is securedin positionploy apluralityfof rivets.,

62.that extend transversely;thiough theside walls.j V

32,S andthebar Bil, These rivets,62..a ls.o serve.; to secure a pair ofangle members-.64.. on. opposite. outer sides oftheitwo side wa1ls.3 2S,and these.

ellisieangies have flanges, sur` that ride :with:

relatively loose slidingaction againstthe inner faces ofthe slidepwalls34S, to serveas a lateral guiding means for the front portion of thechang. nel/34 withvrespect to thefrontporton of the eliarinel?.Initsrear, face, the, `vertical...guideJ,-. bar.: 6.0, besserSemroiroulelt ellide.groovel sus, formedithereia. and .iastaple-driving?.plunger E?,V

isv arranged. to ride' vertically;- alonef this-f smicirqular; guideway.60G.. The; DlungerfxB has therL lower portion thereoicutgawayasati.,and-.aflatl driving platell is secured asby welding; against: .l this.out ,await portionoff` the plungenR so.` tnatr this driving plate;V 'Hlwill ride. againstf; ther rear# wardly flat; faces; ESR of thebloek orbaril); on;l the oppositesideof theguide groove..lzr.'` The@ drivingplateV 'HlA is` thus disposed in;v a., ver-tic 11.,V guideway defined atthe front by the-.svurfaces;i BDR', at the rear by the forward ends; of@the platesv 40 andA the,Y forward end surfaces' of, ther: channel 3.8,and at itsl side edges byv the,si.d s walls 32S,ras will beevident in-Figsllandf 1 end, and below this, head` an expansive.; coil:4 spring 14,surrounds the cylindrical; portion of;y the plunger P. The lower endr ofthis spring;:f[4;-v acts onthe upper end of. the.guide.,bar :60,andz. on.aretaining and guiding, web 18 that'is formed-1f, by extensions fromthe two guiding.. platesflll; The web '18 cooperates with the guidechannel 60G to aord a full circular bearing for, the lindrical upperportion, of the plunger It willv be observed (Fig. .6.) struck lug 341iis alordedinth the-upper channel 3.4, 68H on the bar 6G eng upwardmovement. of theforward end, of the L channel 34 that is causedbythespringlll., In.. theassembly of the tool', the channel'zjismoyed.rearwardly in the channel 34. in,.an amountsuffl. cient to let the hookEDI-I move upwardli7 pastthei: lug-34L-, andl is then returnedtotheileft or fronte-v wardly to align the pivot elements of 'thestrucrvtures. When the plunger P is-inV the upper or fully retracted positionthat is determinedibyq-the engagement-ofthelug 4L withthevhlookjlillIvIgtljieA lower end offthe `Adriving plate 'lll' is disposedljust... above the plane of the upper surfaces?, oflthel staples'l inythe staple guiding channel, ,as will be.; evident in Figs. 2 and 6.Thus, thestaple..adir` vancing A,rneansrwill urge the leading Staple sinto1 a positionimmediatelylbeneath;the staple driving.,r pla-te 1li;andy inthis position the staplewillber. 'disposedV over/the lowerdischarge openingitha afforded-between the forward'end ede'feofthe bottomfwall 32E-andthe reargiace StR; of,t1'i`e,glliole'l baly': The 4lowerportion ofthe plungerQP-isf, preferablycutaway as atfillcgsovthatwhentherV plunger is fully projected, only. the rectangulan; lower endofthe plate 'illwillbe exposed,V

Itwill be observedthat the rounded.upper.isurif:A face of 'the headi l2.of, ,the :plunger P. is.- engagedl. with a relatively thick! and.hardened bearings plate 80.. that v is` xed as by, welding. on theinnen-z surface of. the topv of theextensioru @Eoithefupff.

e front wall MFof ,and ahook shaped. member;y

Per, channeh.; andin the, use l of, the y present ,.tool1,g. theactionoiltlieelements. is such .that.'wlfien.they lower surface of.tlielforgward end of the channelZqf.

is brought into Contact with .tineworlrvv.atithe-gy end of aharnrrieiflilrerstroke, theplungersPzwi-ll be driven downwardly soaastoimpart thlrdes`` de drivingy force to theleading:staples:aslwillbeievifs. dent from Ya comparisonoifFigsiZandf3.foiyitlief4 drawings. In this connectionit.willibeiobser/eda thatthe V forward lowes corner4 .offthegbottom1 walls` 32MB` and ofV the.giviidingfbar 59.; as .well as lthe sides walls SZSfand theangles@filare somewhatzbeveled' androunded as., aty ,82; Eig. 1, therebyytotaio greater latitude in the. zangleat, which` thatool .lnayf`beibrought intolcooperation:withtheworle Sima-- i Theplunger P hasahead. 12 formedat its upper#- that; an'. inwardly:

ages the 1ug.,3,4L.to limit-their I It has been found in practice thatthe present tool operates without any objectionable tendency to mark orscar work at the point where the tool strikes the work, and while theWork must, of course, absorb some of the inertia of the parts, it is theapplicants` present theory that the avoidance of denting or marking ofthe work is due in a large measure to the novel cooperation of theelements of the ram mechanism whereby all binding is avoided.

From the foregoing it will be apparent that the present inventiongreatly simplifies the manufacture of hammer type stapling devices, andthat it enables these stapling devices to be constructed in such a wayas to involve but very few parts that may be manufactured and assembledin a simple and economical manner. It will also be evident that thepresent invention materially simplifies the loading of staples into thestapling tool, and that the parts of the staple holding and loadingmechanism are of a simple character.

It will also be apparent that the present invention enables hammer typestapling devices to be used in many situations where prior devices ofthis type could not be used, since the present device avoids anobjectionable marking or denting of the work surface adjacent to thepoint where the staple is driven.

y Thus, while I have illustrated and described the preferred embodimentof my invention, it is to be understood that this is capable ofvariation and modidcation and I therefore do not wish to be limited tothe precise details set forth, but desire to avail myself of suchchanges and alterations as fall within the purview of the followingclaims.

I claim:

1. In a stapling tool of the hammer type, a pair of elongated channelmembers having front and rear ends and disposed in a reversed relationand one within the other, means pivoting said channels together adjacentsaid rear ends thereof, the inner one of said channels at said front endthereof havingr vertical side walls and a bottom wall formed so thatsaid side walls extend longitudinally beyond the front end of saidbottom wall, a vertically extended guide bar secured between saidextended portions of said side walls and having a at guide surfacefacing toward said rear end of said inner channel, said guide bar havinga vertical guide groove formed therein, a plunger mounted for verticalmovement in said guide groove, spring means urging said plungerupwardly, a driving plate secured on a lower portion of said plunger andriding against said guide surface, staple feeding means for feedingstaples into position against said guide surface and beneath saiddriving plate, and a bearing plate within the upper one of said channelsand bearing against the upper end of said plunger to apply driving forceto said plunger in a harnmer-like driving stroke of said tool.

2. In a stapling tool of the hammer type, a pair of elongated channelmembers having front and rear ends and disposed in a reversed relationand one within the other, means pivoting said channels together adjacentthe rear ends thereof, the inner one of said channels at the front endthereof having vertical side walls and a bottom wall formed so that saidside walls extend longitudinally beyond the forward end of said bottomwall, a vertically extended guide bar secured between said extendedportions of said side walls and having a flat guide surface facingtoward said rear end of said inner channel, said guide bar having avertical guide groove formed therein, a plunger mounted for verticalmovement in said guide groove, spring means urging said plungerupwardly,v a driving plate secured on a lower portion of said plungerand having one face riding against said guide surface, staple guidingand feeding means for feeding staples into position against said guidesurface and beneath said driving plate, said last mentioned meansincluding stationary guiding elements opposing said guide surface andengaging the opposite face of said driving plate, and means within theupper one of said channels affording a bearing surface opposing theupper end of said plunger to apply driving force to said plunger in ahammer-like driving stroke of said tool.

3. In a stapling tool of the hammer type, an elongated channel memberhaving front and rear ends, said channel at the forward end thereofhaving vertical side walls and a bottom Wall formed so that said sidewalls extend longitudinally beyond the forward end of said bottom wall,a vertically extended guide bar secured between said extended portionsof said side walls and having a fiat guide surface facing toward r therear end of said inner channel, said guide bar having a vertical guidegroove formed therein, a plunger mounted for vertical movement in saidguide groove, spring means urging said plunger upwardly, a driving platesecured on a lower portion of said plunger and riding against said guidesurface, staple feeding means disposed within said channel for feedingstaples into position against said guide surface and beneath saiddriving plate, and an elongated housing member substantially enclosingsaid channel and pivoted thereto at the rear end thereof, said housinghaving means thereon disposed opposite the forward end of said channeland bearing against the upper end of said plunger to apply driving forceto said plunger in a hammer-like driving stroke of said tool.

4. In a stapling tool of the hammer type, an enlongated channel memberhaving front and rear ends, said channel at the front end thereof havingvertical side walls and a bottom wall formed so that said side wallsextend longitudinally beyond the front end of said bottom wall, avertically extended guide bar secured between said extended portions ofsaid side walls and having a flat guide surface facing toward the rearend of said inner channel, said guide bar having 'a vertical guidegroove formed in said flat guide Ysurface thereof, a plunger mounted forvertical movement in said guide groove, springs means acting betweensaid guide bar and said plunger to urge said plunger upwardly, a drivingplate secured on a lower portion of said plunger and having one facethereof riding against said guide surface, staple guiding means forguiding staples into position against said guide surface and beneathsaid driving plate, said guiding means including guide elements havingend faces dening guide surfaces for bearing against the opposite face ofsaid driving plate, and a housing pivoted to said channel near the rearend thereof and affording a handle portion at such rear end, saidhousing having means disposed above and opposite said plunger andbearing against the upper end of said plunger to apply driving force tosaid plunger in a hammer-like driving stroke of said tool.

5. In a hammer type stapling tool, an elongated lower channel memberaffording front and rear ends and having side walls and a bottom wallex.. tending from substantially midway between the ends of said sidewalls toa discharge point relatively close to but spaced from theforward ends ofVV said side walls, staple-supporting and guiding 'meansmounted on said bottom wall within said channel and extending to saiddischarge point, spacer means xed between said side walls and extendingfor a substantial distance rearwardly of the staple guiding means inposition to support and guide staples into the rear end of said guidingmeans, spring means operable to urge staples along said guiding meanstoward said discharge point, staple driving means comprising a drivingplunger and a guide block therefor, said guide block being rigidlysecured between said side walls forwardly of-said` discharge point, aspring acting between said block 'and said plunger for retracting saidplunger in an upward direction, a housing surrounding a substantialportion of said lower channel and pivoted theretol at said rear end,said housing having means thereon bearing against the upper end of saidplunger, and means for limiting pivotal movement of said housing-by theretracting spring of said plunger.

6. In a hammer type stapling tool, an elongated lower channel memberaffording front and rear ends and having side walls and a'bottom wallex*- tending from substantially midway between the ends of saidsideWalls to a discharge point relatively close to but spaced from theforward ends of said side walls,'a staple-supporting channel having theweb thereof secured on said bottom wall within said channel so that saidstaple supporting channel extends to said discharge point, the sidewalls of saidV channels being spaced from each other to denne spaces inwhich the legs of staples may depend when the cross members of suchstaples rest on the upper edges of the side walls of said supportingchannel, guide plates secured to the inner surfaces of the side wallsofsaid main channel to hold staples downwardly in position on saidsupporting channel, spacer means xed between said side walls andextending for a substantial distance rearwardly of the staple supportingmeans in position to support and guide staples ontol the rear end ofsaid supporting means, spring means operable to urge staples along saidsupporting means toward said discharge point, staple driving meanscomprising a driving plunger and a guide block therefor, said guideblock being rigidly secured between said side walls forwardly of saiddischarge point, a spring acting between said block and said plunger forretracting said plunger in an upward direction, a housing surrounding asubstantial portion of said lower channel and pivoted thereto at saidrear end, means on said housing bearing on the upper end of saidplunger, and means for limiting pivotal movement of said housing by theretracting spring of said plunger.

'7. In a hammer type stapling tool, an elongated lower member affordingfront and rear ends and having spaced side walls and a bottom wallextending forwardly to a discharge point relatively close to but spacedfrom the forward ends of said side walls, staple-supporting and guidingmeans mounted on said bottom wall between said side walls and extendingto said discharge point, spring means operable to urge staples alongsaid guiding means toward said discharge point, staple driving meanscomprising a driving plunger and a guide block therefor, said guideblock being rigidly secured between said side walls forwardly of saiddischarge point, a spring acting between said block and said 10 plungerfor retracting said plunger in an upward direction, ahousing'surrounding a substantial portion ofsaid lower channeland'pivoted thereto at said rearend, and means for limiting pivotalmovement ofv said housing by the retracting spring of saidplunger.

8.- In a-hammer type stapling tool, an elongated lower member arordingfront and rear ends and having spaced side walls and a bottom wallextending forwardly to a discharge point relatively close to but spacedfrom the forward ends `of'said side walls, staple-supporting andguiding'means mounted on said. bottom wall be'- tween said side wallsand extending to said discharge peint, spring lmeans operable to urgestaples along said` guiding means toward said discharge point, stapledriving means comprising a driving plunger of cylindrical form in itsupper portion andv of semi-cylindrical form in. its lower portion andhaving a flut driving plate Secured to the nat face of saidsemi-cylindrical portion, a guide block secured rigidly between saidvside walls forwardlyv of said discharge point and having asemi-cylindrical guide groove formed vertically inthe rear face thereof,said semi-cylindrical portion of said plunger being guided in saidgroove with said plate bearing against said dat surface of said block, aspring acting between said block and said plunger for retract.- ing saidplunger in an upward direction, a housing surrounding a substantialportion of said lower channel and pivoted thereto at said rear end, andmeans for limiting pivotal movement of said housing by the retractingspring of said plunger.

9. In a hammer type stapling tool, an elongated upper channel formedfrom sheet metal to afford a top wall, front and rear end walls,downwardly extended side walls connectingsaid top and end walls, andguide flanges extended inwardly from the lower edges of said'side wallsthroughout a substantial portion of the length thereof to define spacedparallel guiding edges, an elongated lower channel formed from sheetmetal to afford a bottom wall having front and rear edges, upstandingside walls extended along opposite side edges of said bottom wall andhaving forward extensions beyond said forward edge and rearwardextensions of substantial length extending beyond said rear edge, stapleholding and guiding means mounted within said lower channel in part onsaid bottom wall and in part on said upstanding Side walls, a drivingram, means rigidly secured between said forward extensions for guidingsaid ram vertically past the forward end of said staple holding andguiding means, spring means for retracting said ram, and means pivotingsaid rearward extensions to the side walls of said upper channel todispose said lower channel pivotally on and in part within said upperchannel with said upstanding side walls in sliding guided contact withsaid guide flanges of said upper channel..

10. In a hammer type stapling tool, an elongated upper channel formedfrom sheet metal to afford a top wall, front and rear end walls, sidewalls connecting said top and end walls, and guide iianges extendedinwardly from the lower edges of said side walls throughout asubstantial portion of the length thereof to deiine spaced parallelguiding edges, an elongated lower channel formed from sheet metal toaiford a bottom wall having front and rear edges, upstanding side wallsextended along opposite side edges of said bottom wall and havingforward extensions beyond said forward edge and rearward extensions ofsubstantial length extending beyond said rear edge, staple holding andguiding means mounted within said lower channel in part on said bottomwall and in part on said upstanding side walls, a driving ram, meansrigidly secured between said forward extensions for guiding said ramvertically past the forward end of said staple holding and guidingmeans, spring means for retracting said ram, spacer means xed betweensaid rearward extensions and affording a surface for supporting groupsof staples in alignment with said holding and guiding means when thetool is inverted in the course of a loading operation, and meanspivoting said rearward extensions to the side walls of said upperchannel to dispose said lower channel pivotally on and in partwithinsaid upper channel with said upstanding side walls in sliding guidedcontact with said guide flanges of said upper channel.

l1. In a stapling tool of the hammer type, upper and lower elongatedchannel members disposed 1n reverse relation and one within the other,means for pivoting said channel members together adjacent the re'ar endsthereof, the lower channel member having a bottom wall and Vertical sidewalls extending beyond the front end of the bottom wall, a verticallyextended guide bar secured between said extended portions of said sidewalls and having a ilat guide surface facing towards the rear end ofsaid lower channel member, said guide bar having a vertical guide grooveformed therein, a plunger mounted for vertical movement in said guidegroove, spring means urging said plunger upwardiy, a driving plateextending from a lower portion of said plunger and riding against saidguide surface, and staple feeding means for feeding staples intoposition against said guide surface and beneath the driving plate, theupper member being arranged to apply driving force to said plunger in ahammer-like driving stroke of said tool.

12. In a stapling tool of the hammer type, upper and lower elongatedchannel members disposed in reverse relation and one within the other,means for pivoting said channel members together adjacent the rear endsthereof, the lower channel member having a bottom wall and vertical sidewalls extending beyond the front end of the bottom wall, a verticallyextended guide bar secured between said extended portions of said sidewalls and having a flat guide surface facing towards the rear end ofsaid lower channel member, said guide bar having a vertical guide grooveformed therein and provided at the front with a hook-shaped member, aplunger mounted for vertical movement in said guide groove, spring meansurging said plunger and upper channel member upwardly, said upperchannel member being provided at kthe front end with a lug arranged tobe engaged by said hookshaped member for limiting the upward movement ofthe upper channel member, a driving plate extending from a lower portionof said plunger and riding against said guide surface, and staplefeeding means for feeding staples into position against said guidesurface and beneath the driving plate, the upper member being arrangedto apply driving force to said plunger in a hammer-like driving strokeof said tool.

VALTER E. WEMBER..

REFERENCES CITED The following references are of record in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,687,871 Maynard Oct. 16, 19282,268,102 Attula Dec. 30, 1941 2,311,412 Pankonin Feb. 16, 19432,325,341 Polzer l July 27, 1943 2,342,818 Polzer Feb. 29, 1944

